Duke of Soma (Spanish: Duque de Soma) is a hereditary title in the Peerage of Spain, accompanied by the dignity of Grandee and granted in 1502 by Ferdinand II to Ramón Folch de Cardona, 11th Baron of Bellpuig and 1st Count of Oliveto, for his services as viceroy of Sicily.

[2][3] The name makes reference to the town of Somma Vesuviana, in Naples, Italy.